While a variety of business form assemblies have been proposed and constructed in the past, they normally take the form of a six part form including a fly sheet, the front and back of sheets or plies of the mailer, the front and back plies or sheets of the return envelope and one or more inserts which are conventionally used by the recipient of the mailer for enclosing, for example, with a check in the return envelope, and for record-keeping purposes by the recipient. Assemblies of this type typically therefore include six or more discreet sheets or webs.